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BANCROFT 
LIBRARY 


THE  LIBRARY 

OF 

THE  UNIVERSITY 

OF  CALIFORNIA 


S^^ — =^95 


THE 

ADVANTAGES  AND  NECESSITY 


OF  A 


DEEP  DRAIN  TUNNEL 


i'UK    llll*, 


aHE^T 


COMSTOCK  LEDGE, 


BY  A.   SUTRO. 


.^AiN   l^UA.NCibUU,  i^ElJKUAKY,    1^05. 


^^ ^ ^ 


i 


THE 

ADVANTAGES  AND  NECESSITY 


OF  A 


DEEP  DRim  TUNNEL, 


FOR  THE 


GRE^T 


COMSTOCK  LEDGE, 


BY  Ar.  SUTKO. 

// 

SAN  FKANCISCO,  FEBRUARY,  1865. 


F  ^  4-t> 


CONTENTS. 


Proposition  to  Mining  Companies 

Introductory  Remarks 

The  Great  Obstacle  in  Mining — and  its  Remedy 

Necessity  of  a  Grand  Drain  Tunnel 

The  Tunnell  at  Gittelde,  Brunswick 

Cost  of  Pumping  in  England 

Cost  of  Pumping  in  Nevada 

Evils  of  Pumping 

Advantages  of  a  Drain  Tunnel . 

The  Value  of  the  Mines  will  be  Largely  Increased 

Great  Depth  which  Can  be  Attained  Hereafter 

Report  of  Baron  Richthofen 

Opinion  of  Mining  Superintendents  and  Others 


BANCROFT 
LIBRARY 


TO 


MINING  COMPANIES. 


Tlie  undersinrned  convinced  of  the  necessity  of  constructing  a 
deep  drain  Tunnel  to  the  Comstock  ledge,  and  desirous  of  seeing 
this  great  work  speedily  carried  out,  begs  leave  to  lay  the  fol- 
lowing proposition  before  the  different  Companies  of  the  Com- 
stock ledge,  and  is  of  the  opinion  that  its  acceptance  will  insure 
the  carrying  out  of  this  important  enterprise. 

The  proposition  would  be  about  as  follows  : 
i.v,.uo  trcfc  ihutiexs  ui  juct,  anu  no  wonaer  mat  lau  «iiierprising 

American  people,  particularly  the  adventurous  portion  of  Cali- 
fornians,  became  excited  over  visions  of  great  wealth  and  pic- 
tures of  the  immense  amounts  of  precious  metals  produced  hy 
the  Spanish-American  mines  for  the  last  three  centuries.  The 
natural  consequence  was,  a  great  influx  of  people  to  these 
newly  discovered  regions,  and  a  vigorous  prosecution  of  work, 
which  shortly  established  the  fact  that  the  great  Comstock  ledge 
not  only  contains  ores  of  great  value,  but  that  the  same  ex- 
tends for  miles  in  length,  and  r>rnmigfirLtruJL.^--..^t^- ^ 

The  Companies  will  by  these  means  secure  to  the  Tunnel 
Company  a  small  interest  on  the  capital  Invested.  They  have  to 
pay  out  nothing  until  they  derive  benefit  from  the  drainage  of  their 
mines,  and  then  pay  nothing,  should  they  have  no  ore.  Should  they 
have  ore,  the  amount  to  be  paid  to  the  Tunnel  Company  is  so 
small  compared  to  the  advantages  they  will  derive,  that  they  will 
save  the  amount  to  be  paid  per  ton,  alone  in  the  advantages  they 
would  enjoy  in  extracting  the  ore  from  the  mines. 


If  the  following  pages  are  studied  carefully,  it  will  be  found 
that  the  cost  of  erecting  the  necessary  pumping  machinery,  and 
the  cost  of  maintaining  the  steam  engines,  is  so  immense,  that  the 
advantages  offered  by  the  tunnel  company,  must  strike  the  mining 
companies  to  be  of  vital  importance  to  their  own  interests. 

The  Tunnel  Company  will  have  to  take  all  the  risk  as  to  the 
future  yield  of  these  mines.  They  have  to  embark  in  an  under- 
taking which  involves  the  outlay  of  millions  for  a  number  of 
years,  before  any  benefit  can  be  derived  from  it,  and  after  they 
complete  the  work,  they  only  ask  a  low  interest  on  the  capital 
invested,  from  those  parties  who  can  afford  to  pay,  by  being 
enabled,  through  their  agency,  to  extract  ores  from  their  veins. 

It  may  as  well  be  stated  here,  that  some  parties  are  fearful  of 
getting  into  litigation,  by  having  an  outside  company  construct 
this  tunnel,  and  striking  the  Comstock  at  this  great  depth  ;  on 
this  point  we  would  state,  that  the  objects  of  this  Tunnel  Com- 
Danv  beins  for  the  purpose  of  draining:  these  mines,  they  would 
The  Tunnell  at  Gittelde,  Brunswick 

Cost  of  Pumping  in  England 

Cost  of  Pumping  in  Nevada 

Evils  of  Pumping 

Advantages  of  a  Drain  Tunnel 

The  Value  of  the  Mines  will  be  Largely  Increased 

Great  Depth  which  Can  be  Attained  Hereafter 

"^j  '  "J  '^ir-;Ramn  Richthofen 

people  at  large  of  the  Pacific  states,  oy  st^cuiiu^  mo  pciuiaucut 
working  of  the  Comstock  ledge,  which  in  our  opinion  would  be 
accomplished  by  constructing  a  deep  drain  tunnel,  we  most 
cheerfully  endorse  Mr.  Sutro's  proposition  to  the  Companies, 
and  shall  do  all  in  our  power  to  assist  him  in  carrying  out  his 
project. 

San  Francisco  ^  March  1, 1865. 

JOHN  PARROTT, 
LOUIS  McLANE, 
W.  C.  RALSTON. 


THE  COMSTOCK  imES. 


INTRODUCTORY   REMARKS. 
Over  five  years  have  now  elapsed  since  the  news  of  rich  silver 
mines,  having  been  discovered  on  the  eastern  slope  of  the  Sierra 
Nevada  mountains,  first  attracted  the  attention  of  the  people  of 
California. 

At  first,  {he  reports  of  fabulous  wealth  contained  in  these 
mines,  were  received  with  some  doubt  and  incredulity,  but  soon 
it  became  patent  to  the  miijds  of  thinking  men,  ihat  these  re- 
ports were  matters  of  fact,  and  no  wonder  that  the  enterprising 
American  people,  particularly  the  adventurous  portion  of  Cali- 
fornians,  became  excited  over  visions  of  great  wealth  and  pic- 
tures of  the  immense  amounts  of  precious  metals  produced  by 
the  Spanish-American  mines  for  the  last  three  centuries.  The 
natural  consequence  was,  a  great  influx  of  people  to  these 
newly  discovered  regions,  and  a  vigorous  prosecution  of  work, 
which  shortly  established  the  fact  that  the  great  Comstock  ledge 
not  only  contains  ores  of  great  value,  but  that  the  same  ex- 
tends for  miles  in  length,  and  promised  to  be  of  a  permanent 
character.  This  conclusion  has  proven  correct  by  experience, 
and  we  now  have  a  range  of  mines  which,  in  all  likelihood,  will 
be  worked  long  after  our  present  generation  has  passed  away. 

But  raining  for  silver  was  a  new  thing  for  our  people.  "We 
had  no  experience  at  it ;  hardly  had  any  idea  about  the  opening 
and  working  of  such  mines,  and  not  the  slightest  knowledge 
about  the  reduction  of  silver  ores.  A  few  persons  amongst  us^ 
who  had  acquired  experience  at  foreign  silver  mines,  readily 


6 

gave  their  advice,  and  work  fairly  comraeuced.  But  soon  it  was 
found  that  the  methods  employed  in  older  countries  for  reducing 
ores,  would  not  apply  here,  for  various  reasons,  such  as  the  cli- 
mate, expense  of  labor,  fuel,  etc.,  etc. ;  and  it  became  a  matter  of 
serious  doubt,  whether  these  mines  could  be  profitably  worked  on 
account  of  these  obstacles.  To  ship  the  ores  to  other  countries, 
could  only  apply  to  rich  ores,  the  supply  of  which  w^as  limited. 
To  smelt  the  same  was  out  of  question,  on  account  of  scarcity 
of  fuel.  To  roast,  by  the  Freyberg  method,  was  expensive, 
and  the  bulk  of  the  ores  could  not  stand  the  expense.  To  work 
them  by  patio  was  difficult  on  account  of  cold  weather  the  largest 
portion  of  the  year.  These  were  the  only  methods  known  in  the 
world — none  of  them  applicable  to  our  mines.  What  was  to  be 
done  ?  The  inventive  genius  of  the  American  people  soon  found 
a  remedy  ;  a  trial  was  made  to  work  these  ores  in  iron  pans,  and 
it  was  a  success.  We  must  admit  that  considerable  loss  is  occa- 
sioned in  this  style  of  working,  but  without  it  our  mines  could 
not  be  worked  to  any  advantage,  and  it  is  now  generally  admit- 
ted, that  this  is  the  only  and  most  profitable  method  to  be  em- 
ployed for  average  ores,  which  abound  in  these  mines.  From  the 
day  of  introducing  these  pans,  which,  it  may  be  stated,  have  since 
been  vastly  improved,  the  country  commenced  to  flourish.  Cities 
were  built,  roads  constructed,  large  reduction  works  erected,  in 
short,  from  a  state  of  wilderness,  in  a  few  years,  a  flourishing 
country  sprang  up,  many  millions  of  bullion  are  produced  an- 
nually, and  many  thousands  of  people  find  employment. 

But  not  only  here  do  we  see  the  eflccts  of  this  new  wealth. 
California,  and  particularly  San  Francisco,  are  directly  benefited 
by  it.  Every  branch  of  commerce  derives  benefit  from  our 
mines,  we  being  entirely  dependent  on  our  sister  State  for 
supplies. 

But  will  this  prosperous  state  continue  ?  And  how  long  ? 
No  one  doubts  the  permanency  of  these  mines.  One  particular 
claim  may  run  out  of  its  chimney  of  good  ore ;  one  may  have 
very  rich  ore  at  present,  next  year   its  neighbor  will  have   it. 


Thig  is  the  nature  of  silver  mines  ;  they  contain  bunches,  or 
chimneys  of  ore,  sometimes  producing  many  millions,  but  these 
chimneys  are  distributed  throughout  the  length  of  the  whole 
range,  horizontally  and  perpendicularly.  For  this  reason,  any 
particular  locality  on  a  mining  range  like  the  Comstock,  may 
prove  of  great  value  ;  but  the  expense  of  exploration,  and  the 
difficulties  to  be  encountered  in  prospecting,  make  many  shrink 
from  the  undertaking,  and  give  up  all  hopes  of  realizing  their 
wishes. 

As  long  as  mining  was  carried  on  comparatively  near  the  sur- 
face, everything  went  on  well  enough  ;  a  small  engine  of  10,  20, 
or  thirty  horse  power  was  erected,  at  a  trifling  cost,  a  shaft  sunk. 
a  few  galleries  opened,  plenty  of  ore  extracted,  sent  to  the  mills, 
and  silver  bars  produced,  as  if  by  magic.  But  we  are  a  go  ahead 
people.  What  takes  ten  years  to  accomplish  in  Mexico  or  South 
America,  we  do  in  one  year  ;  and,  as  a  natural  consequence, 
after  five  years'  labor,  we  have  attained  an  average  depth  in  our 
mines  of  four  hundred  feet. 

And  what  questions  do  present  themselves  to  the  thinking 
mind,  now  ?  How  long  will  it  take  to  attain  a  depth  of  one 
thousand,  fifteen  hundred  or  two  thousand  feet  ?  What  obstacles 
are  encountered,  at  present,  and  what  will  be  the  obstacles  to  be 
met  at  this  greater  depth  ?  These  are  serious  questions  to  he  con- 
sidered by  the  owners  of  the  Comstock  ledge,  and  the  people  at  large 
of  this  State,  who  are  entirely  dependent  on  the  prosperity  of  these 
mines. 

And  these  questions,  more  particularly  we  intend  to  answer, 
with  a  view  of  providing  means  to  avoid  a  calamity  which 
would  befall  us  in  a  very  short  number  of  years,  if  we  do  not  at 
once  take  the  matter  in  hand,  and  provide  timely  measures,  the 
nature  of  which  we  intend  iu  this  paper  further  to  explain  : 


THE     GREAT     OBSTACLE     IN     MINING— AND     ITS 

REMEDY. 

The  great  obtade  to  he  enconntered  in  mines,  is  vxUer  ;  this  is  the 
fatal  agent  J  which  makes  it  only  a  question  of  time,  when  a  mine 
will  have  to  be  abandoned,  no  matter  how  rich,  on  account  of 
the  obtacles  its  removal  presents. 

In  every  instance,  the  time  must  com£  when  the  cost  of  drainage 
will  be  greater  than  the  produce  of  the  mine  ;  this  may  take  five, 
ten,  twenty  or  fifty  years,  according  to  the  value  of  the  ores  and 
the  quantity  of  the  water  to  be  encountered. 

Now  let  us  examine  into  our  particular  instance  ;  as  stated 
above,  the  average  depth  of  our  mines  is  about  400  feet ;  hardly 
any  water  of  consequence  has  been  encountered  heretofore  ;  but 
within  the  last  twelve  months,  it  has  become  a  serious  obstacle. 
The  Ophir  mine,  at  present,  is  flooded  in  such  a  manner  that 
their  small  engine  and  pump  cannot  free  the  mine  from  water. 
A  new  and  more  powerful  engine  and  pumps  are  being  erected, 
which,  no  doubt,  will  accomplish  this  desirable  result.  But  how 
long  will  this  machinery  answer  the  purpose  ?  Competent  engi- 
neers will  tell  you,  that  the  power  of  your  machinery  will  have 
to  be  increased  by  the  square,  as  the  depth  and  quantity  of  water 
increases,  and  that  in  the  course  of  not  many  years,  at  the  rate 
we  are  progressing,  our  mines  will  be  worked  at  a  depth  where 
the  cost  of  pumping  will  nearly,  or  entirely,  consume  the  net 
profits  derived  from  them,  basing  our  calculations  on  the  yield 
et  the  present  time. 

These  are  serious  reflections  and  forbode  a  gloomy  future  for  our 
young  State  ;  but  we  will  show  conclusively,  that  a  work,  entirely  feasi- 
ble, practicable,  and  though  of  gigantic  proportions,  can  be  con- 
structed without  any  difficulty,  provided  all  parties  inter- 
ested will  cooperate,  which  will  not  only  remove  all  anxiety  for 
our  future  welfare,  but  which  will  place  our  mines  into  such  a 
position  that  they  may  be  worked  profit-ably,  economically  and  exten- 
sively for  a  centvry  to  come. 


NECESSITY  OF  A  GRAND  DRAIN  TUNNEL. 

This  work  is  the  construction  of  a  Grand  Drain  Tunnel,  com- 
mencing at  a  point  in  the  foot  hills  of  Carson  River  Yalley.  a 
little  less  than  four  miles  or  about  20,000  feet  from  the  Corastock 
ledge,  and  which  Tunnel  would  strike  the  Comstock  ledge  at  a 
depth  of  1800  feet  below  the  surface. 

Works  of  this  kind  have  by  experience  been  found  to  be  a  matter 
of  necessity,  and  have  been  carried  out  wherever  nature  favored 
such  an  undertaking. 

Now  let  us  see  what  has  been  done  in  other  parts  of  the  world 
in  order  to  obtain  drainage  in  mines.  A  late  writer,  speaking  of 
the  completion  of  the  great  dr-iin  tunnel  in  the  Harz  mountains 
in  Germany,  says  : 

"  Already  in  the  beginning  of  the  sixteenth  century,  the  me- 
chanical appliances  for  raising  water  were  found  to  be  insufficient, 
and  it  was  found  to  be  a  matter  of  necessity  to  construct  drain 
tunnels.  The  first  one,  called  the  Seventy-eight  feet  Tunnel,  was 
completed  in  1525,  the  Frankensharner  Tunnel  in  1548,  the  One 
Hundred  and  Fourteen  feet  Tunnel  in  1551  and  the  Raven  Tunnel 
in  1573.  By  means  of  these  Tunnels,  which  were  connected  with 
all  parts  of  the  mines,  it  was  found  possible  to  work  them  for 
about  200  years  ;  but  towards  the  end  of  last  century  it  became 
impossible  to  master  the  water,  and  in  consequence  it  was  con- 
cluded, in  the  year  1771,  to  run  a  still  deeper  tunnel  ;  work  was 
commenced  in  1777  and  the  same  was  completed  in  1799.  It  was 
called  the  Deep  George  Tunnel,  and  its  length,  including  cross 
cuts,  is  57,000  feet ;  it  drains  the  mines  under  Clausthal  to  a 
depth  of  900  feet. 

This  relieved  the  mines  from  water  for  a  while,  but  as  work 
progressed  and  greater  depth  was  attained,  the  flow  of  water 
increased  so  rapidly  that  the  grandest  pump  works  were  found 
to  be  insufficient. 

The  topographical  features  of  the  country  are  fcuch   that  no 
2 


10 

deeper  drainage  could  be  obtained,  except  at  an  apparently  im- 
practicable distance,  and  in  consequence  the  danger  was  imminent, 
that  these  mines,  which  had  supported  thou-ands  of  persons  for 
centuries,  would  shortly  have  to  be  abandoned  entirely. 

THE  TUNNEL  AT  GITTELDE,  BRUNSWICK. 
In  the  year  1850,  C.  Borchers,  a  celebrated  mining  engineer^ 
first  conceived  the  plan  to  commence  a  Tunnel  in  the  Dukedom 
of  Brunswick,  at  a  place  called  Gittelde,  which  would  give  a 
deeper  drainage,  of  about  300  feet,  below  the  deep  George 
Tunnel,  or  a  depth  under  the  cliurch  of  Clausthal,  of 
about  1200  feet.  Surveys  were  made  and  the  distance  found  to 
be  72,000  feet  or  about  fourteen  miles,  and  the  time  estimated  to 
complete  it,  was  twenty-two  years.  On  the  2l8t  July,  1851  work 
on  this  great  tunnel  called  the  "  Ernst  August  Tunnel"  was  com- 
menced, and  on  the  22d  of  June  1864,  the  last  connection  was 
made  ;  It  therefore  only  took  twelve  years  and  eleven  months  to 
complete  this,  the  greatest  of  all  mining  works." 

It  may  as  well  be  stated  here,  that  the  mines  of  the  Harz  pro- 
duce about  $500,000  in  precious  metals  per  annum,  an  amount 
taken  from  the  Comstock  every  fortnight.  Now,  if  they  found 
it  a  matter  of  nercessity.  and  economy  to  run  a  tunnel  fourteen 
miles  long  in  the  Harz  mountains,  in  order  to  obtain  an  addi. 
tional  drainage  of  800  feet,  in  a  country  where  fuel  is  cheap,  how 
evident  must  it  appear,  that  a  tunnel  into  the  Comstock,  less  than 
four  miles  in  length,  which  will  give  drainage  to  a  depth  of  1800 
feet,  and  which  would  secure  the  future  working  of  the  richest 
mine  in  the  world,  would  not  only  prove  of  great  benefit,  but 
ought  to  be  commenced  and  completed  without  delay. 

At  the  place  selected  for  a  starting  |K)int,  the  hills  form  a  semi- 
circle, which  brings  the  distance  from  the  valley  within  four  miles 
of  the  Comstock.  The  formation  of  the  hills  on  the  selected 
tunnel  route,  is  such  that  deep  ravines  exist,  from  which  shafts 
can  be  sunk  at  a  comparatively  small  depth.    The  formation  of 


11 

rock  has  been  examined  by  Baron  Richthofen,  a  well  known 
Prussian  geologist,  who  was  formerly  engaged  at  the  geological 
survey  of  Austria,  and  lately  attached  as  geologist  to  a  Prussian 
naval  expedition  to  eastern  Asia,  and  who  is  a  European  authority 
in  geological  matters.  This  report  is  annexed,  and  will  be  an 
interestitg  document  in  mining  circles. 

It  is  proposed  to  sink  four  shafts  on  the  tunnel  route,  which 
will  be  about  500,  800,  1,100  and  1,£00  feet  deep  to  the  level  of 
the  tunnel,  on  which  powerful  steam  engines  and  pumps  will  have 
to  be  erected,  and  from  each,  two  drifts  will  be  run — one  towards 
the  mouth  of  the  tunnel,  the  other  towards  the  Comstock  ledge. 
This  would  give  nine  points  to  work  from,  and  calculating  the 
distance,  including  shafts,  at  about  24,000  feet,  the  distance  to  be 
sunk  and  run,  would  give  an  average  of  2,666  feet  from  each 
point. 

Work  of  this  kind  can  be  pushed  on  with  great  rapidity,  pro- 
vided, short  and  double  shifts  of  men  are  employed  ;  the  tunnel 
will  be  wide  enough  to  allow  three  men  to  work  abreast,  and  it 
is  proposed  to  employ  double  that  number,  so  that  the  moment 
the  men  at  work  with  their  picks  get  tired,  the  other  three  step 
in  their  places,  and  in  this  manner  change  off  every  fifteen  or 
twenty  minutes  ;  the  whole  shift  to  be  changed  every  six  or  eight 
hours.     A  foreman  would  be  employed  with  each  gang,  whose 
duty  it  would  be  to  see  that  work  is  carried  on  without  any 
interruption,  and  to  discharge  all  hands  who  do  not  perform  their 
task  properly.     In  this  manner  work  can  be  pushed  with  consid 
erable  speed,  and  it  is  the  opinion  of  competent  mining  engi 
neers,  that  at  least  an  average  of  three  feet  per  day  can  be  made 
It  would  therefore  require  888  .days  to  do  the  whole  work 
Allowing  en  extra  year  to  sink  partly  the  deepest  of  the  pro 
posed  shafts,  the  tunnel  can  be  finished  in  3. J  years.     The  shafts 
will  be  located  in  such  a  manner  that  the  deeper  ones  will  come 
nearer  together,  in  order  to  accomplish  a  connection  at  as  nearly 
the  same  time  as  possible  ;  with  that  view,  a  working  survey  is 


being  made  now,  which  will  require  about  one  month  to  com- 
plete. The  proposed  size  of  the  tunnel  will  be  about  12  feet 
wide,  by  10  in  hight,  so  as  to  allow  of  a  good  sized  rail  road 
track,— one  to  run  cars  in.  the  other  to  run  them  out. 

Wherever  hard  rock  is  encountered,  drilling  machinery  will 
be  employed,  which  is  at  the  present  time  used  quite  successfully 
in  Europe,  and  particularly  at  Mount  Ceni?,  in  the  Alps.  This 
drilling  machinery  is  propelled  by  condensed  air,  which  being 
discharged  at  every  revolution,  replenishes  the  air  in  the  tunnel. 

The  above  facts  will  at  once  explain  the  feasibility  of  the  en- 
terprise, and  in  order  to  more  fully  understand  the  difficulties  to 
be  encountered  in  pumping  and  the  advantages  to  be  derived 
from  a  drain  tunnel,  we  will  more  carefully  examine  into  the 
merits  of  each. 

COST  OF  PUMPING  IN  ENGLAND. 

In  order  that  we  may  get  a  correct  idea  of  the  cost  of  pumping 
from  a  great  depth,  and  the  machinery  required  to  do  so,  we  will 
take  the  statistics  of  a  celebrated  mine  in  Europe,  the  "Consoli- 
dated United  Copper  Mines,"  of  Cornwall  : 

They  employ  nine  steam  engines  ;  three  of  90  inch  cylinder  ; 
three  of  85  ;  one  of  80  ;  and  two  of  65  ;  and  a  water  wheel  48 
feet  in  diamater,  all  employed  in  pumping  ;  the  water  discharged 
per  minute  is  from  2,000  to  3,000  gallons.  The  water  is  raised 
at  an  average  of  170  fathoms.  The  average  cost  for  drainage  in 
ten^ears,  has  been,  per  year,  £12,700  sterling. 

The  stream  of  water,  which  would  be  encountered  at  a  depth 
of  1,800  feet,  draining  the  Comstock  ledge  from  the  Siena  Ne- 
vada Mine  to  the  Uncle  Sam,  has  been  variously  estimated  at 
8,  4,  5,  and  as  high  as  10  square  feet,  and  the  rapidity  with 
which  it  would  flow  out  of  the  tunnel,  at  from  5  to  6  miles  per 
hour.  Now  let  us  take  the  lowest  figures  3  square  feet,  and  the 
stream  to  flow  6  miles  per  hour  ;  that  is  to  say,  the  stream  would 


13 

fill  a  trough  or  canal  2  feet  wide,  and  li  feet  high,  and  the 
water  would  flow  5  miles  per  hour.  We  would  then  get  the 
following  figures  :  5  miles  contain  26,300  feet ;  each  foot  in 
length  would  give  3  cubic  feet  or  78,900  cubic  feet  of  water  per 
hour.  This  amount  reduced  to  minutes  gives  1,315  cubic  feet  of 
water  per  minute,  or  8,195  imperial  gallons.  The  cost  of 
draining  the  "C.  U.  Copper  Mines,"  of  Cornwall,  per  annum, 
is  $63,500,  at  a  depth  of  1,020  feet;  at  1,450  feet,  (allowing 
for  tunnels  in  existence  now,)  the  cost  would  be  at  least  one-half 
more,  or  $95,250.  Now  the  quantity  of  water  to  be  raised  here, 
according  to  the  above  estimate,  is  3.28  times  as  much,  which 
would  give  an  annual  cost  of  performing  this  work  in  England, 
of  $312,420. 

The  difference  in  cost  of  fuel,  labor,  etc.,  between  the  state  of 
Nevada  and  Cornwall,  has  variously  been  estimated  to  be  from 
ten  to  fifteen  times  as  much  here,  but  taking  the  lower  figures, 
we  would  get  an  annual  cost  of  draining  these  mines  here,  of 
$3,124,200. 

The  number  of  engines  required  at  theabove][mines  named  in 
Cornwall  is  nine,  of  an  average  diameter  of  cylinder  of  82 
inches  ;  we  would  require  3.28  times  as  many  on  account  of  the 
greater  quantity  of  water  and  again  one  half  as  many  more  on 
account  the  greater  depth  ;  we  would  therefore  require  4.92 
times  as  many  engines,  or  say  44  of  82  inch  cylinder.  The  cost 
of  engines  of  this  size,  including  setting  up,  pumps,  pipes,  etc., 
has  been  estimated  to  be  from  $100,000  to  $150,000  each.  Let  us 
base  our  calculations  on  the  first  named  estimate  :  Forty -four 
engines  at  $100,000  would  give  a  total  cost  of  $4,400,000.  The 
additional  interest,  current  here  above  that  in  England,  would  be 
say  1 J  per  cent,  per  month,  or  on  the  whole  outlay  for  machinery 
$66,000  per  month. 

We  have  now  the  following  amounts  : 

Cost  of  pumping  per  month, $260,350 

Interest  on  capital  invested, 66,000 

Or  a  monthly  expense  of $326,350 

for  drainage  by  pumping. 


14 

Estimating  the  number  of  tons  produced  by  these  mines  to  be 
1000  tons  per  day,  or  30,000  tons  per  month,  the  cost  of  drainage 
per  ton  of  ore  raised,  would  be  $10.88. 

COST  OF  PUMPING  IN  NEVADA. 

In  making  the  above  estimate,  we  have  taken  estimates  of  an 
English  mine  as  our  basis.  Now  let  us  figure  the  cost  of 
pumping,  taking  the  quantity  of  water  as  above  stated  and  make 
our  calculations  from  the  statements  made  by  pumping  works 
and  mills  in  Nevada. 

Most  estimates  are  made  that  the  cost  of  running  a  steam  engine 
for  twenty-four  hours  is  from  $2,00  to  $2,50  per  horse  power. 
Some  are  made  as  low  as  $1,50.  We  will  again  take  the  lower 
figures. 

The  ordinary  way  of  calculating,  is  to  count  33,000  pounds,  to 
be  lifted  one  foot  high  per  minute,  as  one  horse  power. 

We  have  8195  gallons,  or  1315  cubic  feet,  at  62.32  pounds 
per  cubic  foot,  we  get  81,950  lbs  to  be  lifted  per  minute  ;  divided 
by  33,000,  this  would  give  27.80  horse  powers,  to  lift  the  given 
quantity  one  foot  high  ;  in  order  to  lift  it  1450  feet,  we 
have  to  multiply  by  that  number,  which  would  give  4039  horse 
powers.  Now  it  takes  just  double  the  given  power,  to  overcome 
the  friction  of  water  in  pipes,  the  friction  of  engine,  etc.,  etc., 
which  would  give  8078  horse  powers,  to  raise  the  given  quantity 
of  water  1450  feet.  Calculating  the  cost  of  running  the  pump- 
ing machinery,  as  stated  above  at  $1,50  per  day  per  horse  power, 
we  would  have  an  expense  of  $12,117  per  day,  or  $363,510  per 
month,  or  on  every  ton  of  ore  raised  an  expense  of  $12,12. 

Some  statistics  have  been  furnished  by  Capt.  Taylor  of  the 
Best  <fe  Belcher  mine  whose  pumping  works,  are  among  the  best 


y/^  irc^  f 


15 

and   most  economically  conducted  in  Nevada.     He   gives  the 
followino^  account  of  daily  expenses  in  pumpino;  : 

In  consequence  of  these  accidents,  the  mine  will  be  flooded 
frequently,  and  delays  occasioned  of  days,  weeks,  or  even  months, 
throwing  the  miners  out  of  employ,  stopping  the  mills,  and  cut- 
ting ofi"  looked  for  dividends  ;  thus  creating  great  hardships  in 
all  quarters. 

But  this  is  not  the  only  evil  arising  therefrom  :    the  filling  of 
The  engineers  and  pitmens  wages  would  be  considerably  less  in 
large  pumping  works,  but  not  having  brought  into  account  any 
allowance  for  wear  and  tear,  this  will  be  nearly  balanced. 

He  raises  the  water  270  feet  and  discharges  253  gallons  per 
minute.  At  1450  feet,  the  water  would  be  raised  5.37  times 
as  high,  which  would  give  a  daily  expense  of  $472,56.  The 
quantity  of  water,  from  the  whole  length  of  the  Comstock  ledge 
at  1800  feet,  would  be  32.39  times  as  much,  making  a  daily 
cost  of  $15,306,21,  or  an  expenditure  per  month  of  $459,186,30, 
or  per  ton  of  ore  $15,36. 

RECAPITULATION. 

Cost  of  pumping  the  estimated  water  from  a  depth  of  1,800 
feet  under  the  surface  : 


Cu&t  per  lou  taking: 
the  yield  at  30,000 
tons  per  month. 

Coat  per  day. 

Cost  per  month.  Cost  per  annum. 

CalculatiooB  based  «)n  the 
cost  at  the  Connolidated 
United  Copper  Mines  of 
C  .rnwall. 

$10.83.                    $10,878. 

$326,360. 

$3,916,S0O. 

Calcuiutioiia  based  on  cost 
of  running  8team  en- 
frines  in  Nevada. 

$12.12.                     $12,117. 

$363,510. 

$4,362,120. 

CalculaiionH  based  on  the 
cost  of  pumping  at  the 
Best  &  Belcher  Mine, 
Nevada. 

$15.36. 

$15,306. 

$459,186. 

$5,600,232. 

These  are  astonishing  figures,  but  they  are  nevertheless  correct; 
but  even  one  half,  one  third,  or  one  quarter  of  these  amounts  will 
give  sums,  so  immensely  large,  that  a  system  of  drainage  by  tun- 
nelling must  appear  to  be  a  matter  of  necessity. 


16 

Many  persons  not  acquainted  with  mechanics  and  engineering, 
will  be  at  a  loss  to  understand  why  it  costs  so  much  to  pump  from 


COST  OF  PUMPING  IN  NEVADA. 

In  making  the  above  estimate,  we  have  taken  estimates  of  an 
English  mine  as  our  basis.  Now  let  us  figure  the  cost  of 
pmnpiog,  taking  the  quantity  of  water  as  above  stated  and  make 
feet,  it  would  require  nine  such  engines  and  pumps  to  lift  the 
same  quantity  of  water  from  a  depth  of  1,800  feet.  The  water 
is  raised  by  the  first  pump  200  feet  high,  from  the  lowest  point,  and 
discharged  into  a  reservoir  ;  from  thence  it  is  lifted  by  another 
pump  to  a  point  200  feet  higher,  and  so  on  until  it  reaches  the 
surface.  We  must  therefore  have  nine  engines  to  do  this  work ; 
and,  if  we  calculate  the  quantity  of  water,  which  would  be  met 
at  1,800  feet,  to  be  three  limes  the  quantity  met  at  200  feet,  we 
would  require  twenty-seven  engines,  of  fifty-horse  power,  to  pump 
out  a  single  mine  at  that  depth,  where  only  one  is  required  now. 

The  above  estimates,  give  simply  the  cost  of  pumping  out  the 
continuous  flow  of  water.  It  must  be  borne  in  mind  though, 
tliat  the  body  of  accumulated  water  at  present  contained  in  the  ledge^ 
where  large  subterreanean  reservoirs  or  lakes  are  known  to  exists  is 
very  large.  In  order  to  remove  this  great  body  of  water,  at  least 
twelve  months  would  be  required,  employing  all  the  above 
enumerated  engines,  at  a  cost  of  running  them,  for  that  length  of 
time,  of  from  $3,000,000  to  $4,000,000. 

EVILS  OF  PUMPING. 

Independant  of  the  actual  cost  of  pumping,  there  are  other  dis- 
advantages connected  with  the  same,  which  must  not  be  lost  sight 
of.  Enginesj  boilers,  pumps,  etc.,  etc.,  rapidly  wear  out,  and  new 
ones  have  to  take  their  places  in  the  course  of  time  :  pumps  are 
liable  to  get  out  of  order  at  any  time,  and  they  being  placed  at 
the  very  lowest  point  in  the  mine,  if  not  instantly  repaired,  the 


17 

water  will  rise  above  them  and  then  it  is  impossible  to  reach  the 
pump  in  order  to  lepair  it. 

In  consequence  of  these  accidents,  the  mine  will  be  flooded 
frequentl.v,  and  delays  occasioned  of  days,  weeks,  or  even  months, 
throwing  the  miners  out  of  employ,  stopping  the  mills,  and  cut- 
ting oft'  looked  for  dividends  ;  thus  creating  great  hardships  in 
all  quarters. 

But  this  is  not  the  only  evil  arising  therefrom  :  the  filling  of 
the  chambers  and  galleries  with  water  swells  the  ground  and 
timbers,  which  after  the  water  is  removed  shrinks,  and  conse- 
qaenily  leaves  the  mine  in  an  insecure  state,  making  it  liable  to  cave 
in.  The  timbers,  undergoing  these  changes,  decay  sooner,  and 
must  be  renewed  oftener  in  consequence.  Miners  in  distant 
parts  of  the  mine  remain  in  a  constant  state  of  anxiety,  fearing 
some  accident  to  the  pumps  ;  they  certainly  do  not  work  with 
that  feeling  of  security  they  would  otherwise  posess. 

Another  objectionable  feature  of  pumping  is,  the  fact  that  the 
mine  which  reaches  the  greatest  depth  is  compelled  to  do  all  the 
pumping,  not  only  for  itself,  but  also  for  its  neighbors,  thus  drain- 
ing them  without  receiving  any  remuneration.  This  will  retard 
mining  operation?  to  a  large  extent,  as  many  companies  would 
prefer  to  suspend  the  working  of  their  mines  until  the  adjoining 
claims  have  reached  the  same  level,  in  order  to  bring  them  to 
equitable  terms.     A  drain  tunnel  will  avoid  all  these  difficulties. 

ADVANTAGES  OF  A  DRAIN  TUNNEL. 

As  to  the  advantages  derived  from  a  drain  tunnel,  at  this  great 
depth,  we  will  enumerate  a  few : 

Shafts  can  at  once  be  sunk  the  whole  depth  connecting  with 
the  tunnel,  thus  insuring  the  most  thorough  ventilation  ;  this  is 
a  matter  of  great  importance  in  deep  mines  ;  the  health  of  the 
miners  is  thereby  secured  and  they  can  work  along  with  vigor 
and  energy,  not  being  stifled  with  fumes  of  powder  and  foul  air  j 
3 


18 

and  it  is  a  fact,  ascertained  by  experience,  that  they  will  per- 
form one-half  more  work,  which  reduced  to  dollars  and  cents 
will  make  an  immence  saving  in  the  course  of  the  year. 

THE   VALUE    OF   THE    IMINES   WILL    BE   LARGELY 
IXCKEASED. 

At  present  the  value  of  a  mine  is  estimated,  to  a  large  extent, 
by  the  body  of  ore  actually  in  sijrht,  and  very  few  of  them  have 
explored  their  pay  ore  to  more  than  one  hundred  feet  in  depth. 
After  this  drain  tunnel  is  completed,  nothing  will  prevent  the 
mines  from  being  opened  at  once  to  the  whole  depth  of  1,800 
feet,  shotving  the  different  bodUs  of  ore  contained  in  the  surne, 
exposing  milUmis  of  dollars  to  the  eye,  and  thus  increasing  their 
value  in  proportion.  Having  thus  thousands  of  tons  of  ore  Id 
Fight,  preparation?  can  be  made  to  work  the  same  in  an  econom- 
ical manner,  nnd  mills  can  be  creeled  with  perfect  security. 

Many  advantages  would  arise  from  the  more  perfect  system  of 
mining  and  timbering,  which  could  be  adopted  ;  it  could  bedono 
more  systematically  and  economically  than  at  present. 

Hauling  being  ver)  expensive,  quite  a  considerable  saving 
would  arise  from  the  fact  that  the  ore  in  a  well  drained  mine  is 
nearly  dry.  At  present  about  10  per  cent,  of  water  is  contained 
in  the  ore  as  hauled  to  the  mills,  and  calculating  the  average  cost 
of  hauling  at  $4  per  ton,  this  would  save  40  cents  on  every  ton,  or 
$400  per  day,  or  the  large  sum  of  $144,000  per  annum. 

Particular  advantages  would  arise  to  those  claims  on  the  Corn- 
stock  ledge,  who  never  have  found  any  ore  yd,  or  who  have  run  out 
of  it.  They  are  tired  of  paying  assessments,  and  their  mines 
will  probably  not  bo  prosi)ected  for  many  yeai-H  to  come.  This 
drain  tunnel  will  enable  them  to  explore  their  claims  at  a  great 
depth,  atjout  a  small  expense  ;  and  there  is  every  reason  to  think 
that  many  of  them  will  prove  of  great  value. 


19 

GREAT  DEPTH  WHICH  WILL  BE  ATTAINED  HERE- 

AFTER. 

The  mines  can  be  worked  a  great  depth  below  the  level  of  this 
tunnel  by  pumping  the  water  into  the  same.  This  is  accom- 
plished in  Europe,  in  a  very  ingenious  manner,  at  comparatively 
small  expense,  by  collecting  the  water  in  the  upper  parts  of  the 
mine  in  reservoirs  and  conducting  it  in  pipes  to  hydraulic 
engines  placed  at  the  level  of  the  tunnel  ;  thus  using  a  portion  of  the 
very  water  which  causes  all  the  obstacles  at  present,  as  a  most  useful  and 
economical  motive  power  to  propel  pumps  ;  tohich,  in  their  turn 
raise  the  wafer f. am  ^reat  depths  below.  It  may  safely  be  stated, 
therefore,  that  by  means  of  this  tunnel  the  Comstock  ledge  can 
profitably  be  worked  to  a  depth  of  at  least  3,000  feet. 

The  necessity  of  completing  this  tunnel,  without  delay,  must  be 
apparent  to  every  one  who  reads  these  pages  attentively,  and 
gives  this  important  subject  the  attention  it  deserves.  No  time 
ought  to  be  lost  to  commence  operations  at  once,  and  to  push  the 
same  with  the  greatest  energy,  day  and  night,  until  completed. 
By  the  time  this  work  can  possibly  be  finished,  the  decline  of  our 
mining  interests^  and  all  other  interests  in  JVevada,  will  fairly  have 
commenced.  If  this  matter  is  delayed  until  the  mines  cannot  be 
worked  any  deeper  by  machinery,  the  country  will  go  to  ruin, 
waiting  for  a  drain  tunnel  to  be  completed. 

Much  has  been  spoken  and  written  about  the  importance  of  a 
railroad  across  the  mountains  ;  it  has  been  the  subject  of  dis- 
cussion in  the  newspapers,  in  the  Halls  of  the  Legislature,  and  in 
Congress,  for  a  number  of  years  past.  It  is  certainly  a  subject 
of  great  interest  to  the  people  of  Nevada  and  California.  But 
this  tunnel  is  of  still  greater  im,portance,  for  we  venture  to  say,  that 
but  few  people  would  be  in  JYevada  by  the  time  a  railroad  is  finished, 
if  this  tunnel  is  not  constructed. 

Every  person  owning  in  the  Comstock  ledge  is  deeply  inter- 
ested in  the  carrying  out  of  this  enterprise,  and  so  is  every  resi- 
dent of  the  State  of  Nevada  ;   whether  miner,  merchant,  farmer, 


20 

banker,  teamster,  millman,  or  of  any  other  occupation.  But  the 
people  of  California,  and  particularly  San  Franci?co,  are  not  the 
less  interested  ;  every  dollar  produced  by  these  mines  finds  its 
way  to  California,  in  exchange  for  its  produce. 

It  is  a  gratifying  fact  to  the  undersigned  that  this  important 
undertaking  is  commencing  to  be  appreciated  by  all  intelligent^ 
persons  who  go  to  the  trouble  to  investigate  its  merits.  He  has 
for  several  years  past  endeavored  to  explain  its  importance,  but 
could  find  no  encouragement  whatever  to  carry  it  out. 

But  it  is  apparent  that  the  proper  time  has  now  arrived  to  carry 
out  this  great  work.  Persons  who  never  dreamed  of  the  difficul- 
ties to  be  encountered  from  water  in  (working)  mines,  commence  to 
realize  the  importance  of  drainage  and  have  become  enthusiastic 
friends  of  this  enterprise. 

The  attention  of  many  has  been  drawn  towards  this  under- 
taking, by  the  fact  that  the  Nevada  Legislature  has  of  late  granted 
the  undersigned  the  exclusive  privilege  for  fifty  years,  to  construct 
a  tunnel  from  the  valley  of  Carson  river  ;  he  is  fully  determined 
to  overcome  all  obstacles,  should  any  present  themselves,  and  feels 
satisfied  that  with  the  assistance  of  the  many  friends  of  this  enter- 
prise, the  day  will  soon  arrive  when  work  will  fairly  be  commenced* 

A.  SUTRO. 
San  Francisco,  February  24.  1865. 


REPORT  OF  BARON  RICHTHOFEN. 

Virginia,  February  16,  1865. 
A.  SuTRO,  Esq.,  Dayton : 

Dear  Sir  : 

I  learned  with  great  interest  of  your  magnificent  project  to 
run  a  deep  drain  tunnel  to  the  Comstock  vein,  from  a  place  near 
the  mouth  of  Webber  Canon,  three  and  a  third  miles  north  of 
Dayton,  and  I  cheerfully  comply  with  your  request  to  state  to 
you  my  views  about  the  importance  and  feasibility  of  this  enter- 


•21 

prise.  Its  value  will,  of  course,  chiefly  depend  upon  the  question 
whether  these  mines  will  ever  be  worked  to  considerable  depth ; 
that  is,  whether  the  Comstock  vein  will  extend  far  down,  and 
whether  it  will  retain  its  metallifferous  character  in  depth.  Both 
questions  have  to  be  decided  from  the  stud}^  of  the  structure  and 
nature  of  the  Comstock  vein,  and  from  comparing  the  results 
with  the  observations  at  such  mines  in  other  countries,  which 
have  already  been  worked  to  great  depth.  My  experience  on 
the  Comstock  vein  is  based  on  close  and  repeated  examinations 
of!  nearly  all  the  mines  on  its  course.  I  believe,  to  concur  with 
almost  everybody,  who  has  equal  experience  about  them,  in  the 
opinion,  that  it  is  a  true  fissure  vein,  of  extraordinary  length,  and 
extending  downward  much  farther  than  any  mining  works  will 
ever  be  able  to  be  carried  on.  It  would  be  too  lengthy  to 
enumerate  the  various  reasons  which  lead  most  positively  to  this 
conclusion.  It  is  now  assumed  almost  universally  as  a  fact,  and 
the  number  of  those  who  consider  it  as  a  gash  vein,  or  a  system 
of  gash  veins,  is  fost  diminishing. 

As  to  the  downward  continuance  of  the  ore  bearing  character, 
every  instance  goes  to  show  that  the  average  yield  in  precious 
metals  remains  about  equal  at  every  depth.  Some  mines  had 
accumulations  of  ore  near  the  surface  (Ophir,  Mexican,  Gold 
Hill),  in  others  they  commenced  very  near  under  the  surface 
(Gould  &  Curry,  Potosi,  Yellow  Jacket,  Belcher),  at  others, 
again,  considerable  work  had  to  be  done  before  bodies  of  ore  of 
any  amount  were  struck  (Chollar,  the  southern  part  of  Gold 
Hill,  Uncle  Sam,  and  others),  and  some  which  had  no  ore  hereto- 
fore, appear  to  have  good  prospects  to  find  it  soon.  The  fact 
that  some  rich  bodies  of  ore,  which  were  found  near  the  surface, 
gave  out.  at  the  depth  of  a  few  hundred  feet,  induced  the  com- 
mon belief,  that  the  Comstock  vein  was  becoming  poorer  in  its 
lower  parts.  But  the  explorations  of  the  last  months  have 
entirely  defeated  this  opinion.  On  the  contrary,  the  enormous 
amount  of  bullion,  which  is  being  produced  by  the  mines  at 


22 

present,  may  almost  appear  to  prove  that  the  vein  is  improving 
in  depth.  But  this  conclusion  is  probably  equally  fallacious,  as 
it  must  be  borne  iu  mind  that  many  mines  have  been  developed 
at  different  levels,  and  ore  is  being  extracted  from  several  of 
those.  Hoisting  works,  and  the  mode  of  extracting  the  ore, 
have  also  been  improved,  and,  of  course,  help  to  increase  the 
daily  produce.  This  average  equality  of  the  produce  of  the 
vein  at  every  different  level,  is  not  only  true  for  the  amount  of 
ore  extracted,  but  also  for  ils  yield.  The  rich  body  of  ore  in  the 
Ophir  and  Mexican  mines,  forms  the  only  exception  to  this  rule, 
as  none  of  equal  average  percentage  in  silver  and  gold  has  been 
found  again.  Even  the  relative  proportion  of  gold  and  silver  in 
the  ore  has  not  undergone  any  material  change,  though  the 
bullion,  on  account  of  the  more  imperfect  processes  of  reduction, 
contained  at  first  proportionally  more  gold  than  at  pre- 
sent. The  ore  found  in  the  Uncle  Sam  mine,  at  the  depth 
of  414  feet,  is  as  rich  in  gold  as  any  found  in  other  parts  within 
100  feet  from  the  surface. 

There  is  no  reason  to  doubt  that  this  equality  of  average  pro 
duce  and  yield  thoughout  the  entire  le^ngth  of  the  vein,  will  con- 
tinue downward  to  any  depth.  Besides,  the  very  obvious 
theoretical  conclusion  that  vast  amounts  of  silver  could  not  be 
carried  into  the  fissure  from  the  overlying  or  the  enclosing  rocks, 
but  naturally  had  to  rise  from  unknown  depth,  through  the  chan- 
nel of  tiie  fissure  itself,  to  be  deposited  in  it  wherever  the  condi- 
tions for  sublimation  or  precipitation  were  given  in  its  open 
space.  Experience  in  other  countries  by  no  means  shows  of  a 
regular  decrease  or  an  increase  in  yield  as  of  common  occurrence, 
though  either  of  them  may  happen.  More  commonly,  the  pro- 
duce of  true  fissure  veins  in  precious  metals,  has  been  found  to 
be  about  constant. 

It  is,  notwithstanding,  a  well  known  fact,  that  the  profits  of 
silver  and  gold  mining  decrease  rapidly  in  reacliing  deeper 
levels.    The  magnificent  silver  veins  in  the  Karpathians,  for  in- 


23 

stance,  which  are  the  only  ones  in  Europe,  closely  resembling  the 
Comstock  vein,  have  been  worked  formerly  with  great  profit,  and 
pay  now  but  little  above  their  expenses.  But  this  is  principally 
due  to  the  increased  expense  in  working  them.  Drainage  is  the 
heaviest  item,  mostly  where  the  water  has  to  be  raised  to  a  great 
hight.  It  devours  so  much  of  the  produce,  that,  with  increasing 
depth,  the  net  profits  will  be  diminished,  then  totally  absorbed, 
and,  finally,  exceeded  by  the  cost  of  raising  the  water.  Drain 
tunnels  have,  therefore,  been  constructed  wherever  it  could  be 
done  with  a  reasonable  expense,  provided  the  veins  could  be 
struck  at  a  considerable  depth.  It  appears  that,  for  the  Com- 
stock vein,  the  day  is  not  far  distant  when  the  expenses  of  rais- 
ing water  will  be  so  large,  that  a  great  quantity  of  those  middle 
class  ores,  which  are  the  principal  source  of  wealth  of  these 
mines,  will  no  more  yield  any  profits,  and  the  benefits  from  the 
richer  ores  will  also  be  diniinished  ;  and,  if  mining  in  this  fast 
country  proceeds  as  rapidly  towards  lower  levels  as  it  did  here- 
tofore, it  will  have  to  be  abandoned  after  some  years,  if  the 
difficulty  is  not  met  with  by  the  means  proposed  by  you.  It  is 
useless  for  me  to  dwell  upon  the  great  benefits  which  the  mines 
would  derive  from  the  construction  of  a  deep  drain  tunnel. 
Calculations  on  a  very  moderate  basis  show  the  advantages  by 
plain  figures  so  ohviously  as  to  strike  every  thinking  mind. 

The  second  subject  about  which  you  requested  me  to  state  my 
views,  is  the  practical  feasibility  of  your  project.  The  best 
starting  point  of  the  drain  tunnel  will  of  course  be  at  such  a 
place,  where  the  greatest  possible  depth  on  the  vein  can  be 
reached  by  the  shortest  possible  route.  Besides,  it  has  to  be 
taken  into  consideration,  which  qualities  of  rock  the  tunnel 
would  have  to  run  through,  and  which  are  the  facilities  for  sink- 
ing air  shafts.  I  will  try  to  argue  these  different  points,  as  my 
numerous  geological  examinations  and  rambles  over  the  country 
of  Washoe  have  made  me  pretty  familiar  with  its  physical  out- 
lines and  its  geological  structure. 


BANCROFT 
LIBRARY 


24 

As  to  the  starting  point  of  the  drain  tunnel,  you  hate,  with 
remarkable  sagacity,  selected  a  place  which  so  far  supercedes 
any  other,  as  to  be  indeed  the  only  feasible  one  in  the  country. 
South  of  Webber  Canon,  the  range  of  hills  which  slope  into 
Carson  Valley,  recedes  in  the  shape  of  an  amphitheatre,  and 
allows  the  almost  level  bottom  of  the  desert  to  approach  the 
Comstock  vein  within  less  than  four  miles.  The  level  of  the 
Carson  river  at  Dayton,  is  about  1900  feet  lower  than  the  crop- 
pings  of  the  Comstock  vein  at  the  Gould  &  Curry  office.  If  the 
tunnel  starts  100  feet  above  the  river,  at  the  foot  of  the  hills, 
it  will  strike  the  Comstock  vein  1800  feet  below  those  croppings. 
Making  no  allowance  for  the  Eastern  dip  of  the  vein,  its  length 
would  be  about  19,000  feet ;  thus  making  the  proportion  of  depth 
to  length,  as  I  to  10.65. 

There  is  no  place  more  suitable  along  the  banks  of  Carson 
river.  A  tunnel  from  the  lower  part  of  Gold  Canon  (below 
Johntown,)  would  have  to  run  22,000  feet  to  the  Divide,  and  25,- 

000  feet  to  the  Gould  &  Curry  cropping^  besides  starting  be- 
tween 200  and  300  feet  higher  than  the  place  selected  by  you. 
and  offering  great  disadvantages  as  to  the  qualities  of  rocks  and 
the  sinking  of  air  shafb^.  A  third  place  which  might  be  selected 
for  starting,  would  be  at  the  bottom  of  the  canon  which  extends 
from  the  Santiago  Mine  down  to  the  New  York  House.  You 
would  strike  by  such  tunnel  the  central  part  of  American  Flat 
at  11,000  feet,  the  Gould  <fe  Curry  croppings  at  24,000  ;  but  com- 
paring with  the  place  near  the  mouth  of  Webber  Caiion,  you 
would  lose  about  600  feet  in  depth. 

The  disadvantages  of  running  a  tunnel  from  Washoe  Valley 
or  Steamboat  Springs,  to  the  Comstock  vein,  are  so  obvious  that 

1  need  not  dwell  upon  them.  Those  places,  are,  respectively, 
about  1300  and  IfiOO  feet  lower  than  the  Gould  and  Curry 
croppings  ;  the  distance  of  the  former  from  the  same  croppings 
is  about  30,000,  that  of  the  latter  about  40,000  feet.  Both 
places  can  never  compete  with  any  on  the  Carson  river  :  and 


25 


besides  their  great  distance  and  comparatively  little  depth,  you 
would  have  to  run  through  extremely  hard  rocks,  and  would 
never  be  able  to  sink  air  shafts. 

The  three  places  in  Carson  Valley,  will  compare  as  follows  : 


starting  Point. 

Length   of  tunnel  to 
Gould  &  Curry  cropp. 

Depth    below    Gould 
&  Curry  cropp. 

Proportion  of  depth 
to  length. 

1.     Near    mouth    of    Webber     ") 
Canon,  3)^  miles  north  of  Day-      Ubout  19,000  feet, 
ton.                                                        J 

about  1800  feet. 

1:  10.55. 

2.     In     Gold      Canon,     below 
John  town. 

J     "      26,000      '• 

"      1500      '• 

1:  16.66. 

3.     In    Canon    from    Santiago 
Mine  to  Xew  York  House. 

1     "      24.000      « 

"       1200      " 

1:  20.00. 

Though  these  figures  are  but  aproximations,  they  show  plainly 
the  great  superiority  of  the  place  selected  by  you. 

The  facilities  of  excavating  the  tunnel  will  mainly  depend 
upon  the  quality  of  the  rocks  through  which  it  will  pass.     It  is 
a  remarkably  fortunate  incidence  that  the  route  selected  by  you 
promises,  also,  in   this  respect,  to  be  the  most  advantageous. 
While  the  tunnels,  both  from  Gold  Canon  and  from  New  York 
Canon,  would  have  to  pass  to  great  extent  through  quartzose 
porphyry,  which  is  the  hardest,  and    through  a   certain  kind 
of  metamorphic  rock,  which  is  the  toughest  rock  of  the  country f 
you  will  not  meet  either  of  these  rocks.     The  first  6000  or  7000 
feet  will  be  run  through  trachyte  and  trachytic  breccia  which  in  a 
broad  semicircular  belt  of  prominent  hills,  swing  from  Dayton  by 
the  Sugarloaf  to  Washoe  Valley.     Trachytic  breccia  can  easily 
be  worked  by  the  pick,  yet  is  ordinarily  solid  and  dry  enough  to 
require  no  timbering.     You  may  form  an  idea  of  its  excellent 
qualities  for  tunneling,  from  the  fact  that  in  Hungary  wine  cellars, 
hundreds  of  feet  in  length,  are  with  preference  excavated  in  this 
kind  of  rock.     The  solid  trachyte  is  an  excellent  blasting  rock. 
Its  superior  qualities  have  caused  its  general  use  in  Washoe  for 
building  material  ;  it  was  applied  as  such  in  the  construction  of 
the  solid  masonry  of  the  Gould  &  Curry  Mill.     With  the  use  of 


26 

the  drilling  machine  of  Mount  Cenis  you  will  make  speedy  work 
in  this  rock. 

The  next  2,500  feet  will,  to  all  probability,  exhibit  a  great 
variety  of  rock,  some  of  which  will  be  rather  hard.  This  applies 
chiefly  to  certain  volcanic  rocks  of  dark  color  (andesite),  which 
flank  the  trachytic  range  to  the  west;  but  as  they  occur  in 
dykes  parallel  to  the  same,  they  will  retard  work  but  slightly. 

The  following  10,000  feet,  which  bring  you  to  the  vein,  will 
most  likely  consist  of  the  same  material  as  is  traversed  by  the 
numerous  tunnels  which  lead  at  present  to  the  Comstock  vein. 
This  rock  (trachytic  greenstone)  would  ofi*er  serious  obstacles  if 
it  was  in  an  undecomposed  state.  But  from  the  general  nature 
of  its  decomposition,  which,  evidently,  was  performed  from  be- 
low, by  ascending  steam  and  vapors,  during  a  time  of  volcanic 
action,  I  believe  to  be  justified  in  the  conclusion  that  you  will 
find  it  for  the  entire  length  of  10,000  feet  of  the  same  rotten  na- 
ture, as  in  the  shallow  tunnels  at  present  in  existence.  It  varies 
in  them  constantly,  some  varieties  being  easily  worked  by  the 
pick,  while  others,  occurring  in  streaks  parallel  to  the  vein,  are 
less  decomposed,  and  have  to  be  blasted.  Timbering  would 
probably  be  required  but  to  a  limited  degree  in  a  small  tunnel  ; 
but  if  you  make  it  of  sufficient  size  for  a  double  track,  you  may" 
have  to  timber  almost  all  of  the  10,000  feet. 

A  third  requirement,  though  not  absolutely  necessary  with 
the  present  accomj)lishments  of  tunneling,  will  be  the  sinking  of 
air-shafts.  Also,  in  regard  to  these,  your  tunnel  offers  greater 
facilities  than  any  other  route.  It  passes  first  under  a  high 
range  of  hills,  which  is  accompanied  on  either  side  by  deep 
ravines.  Each  of  them  will  be  a  suitable  starting  place  for  an 
air-shaft ;  the  depth  of  the  latter  would  be  about  500  and  750 
feet;  The  first  of  the  two  would  be  about  3,000  feet  distant 
from  the  mouth  of  the  tunnel,  the  second  about  3,600  feet  from 
the  first.  Approaching  the  Comstock  vein,  there  are  two  more 
places  suitable  for  air-shafts,  the  distance  from  tlie  second  to  the 


27 

third  being  2,500  feet,  that  of  the  third  to  the  fourth,  4,000  feet, 
thus  leaving  about  6,000  feet  distance  from  the  fourth  shaft  to  a 
point  vertically  under  the  Gould  and  Curry  croppings.  The  two 
last  shafts  would  have  a  depth  of  1,200  and  1,300  feet.  One  of 
them  will,  no  doubt,  be  sufficient. 

None  of  ihe  prominent  mining  countries  of  the  world  can 
boast  of  equal  facilities  for  a  drain-tunnel.  I  do  not  know  of 
any  that  drains  mines  at  an  equal  depth,  and  yet,  many  drain- 
tunnels  have  more  than  double  the  length  of  the  one  proposed  by 
you.  If,  in  the  Harz  mountains,  where  labor  and  fuel  are  cheap, 
it  was  considered  economical  to  construct  a  drain-tunnel  of 
72,000  feet  in  length  for  draining  the  mines  to  the  depth  of 
1,200  feet,  all  this  for  a  product  which  is  scarcely  one-thirtieth 
of  that  of  Washoe,  how  much  more  economical  must  it  be  in  the 
latter  country,  with  its  enormous  value  of  labor  and  fuel,  to  run 
a  drain-tunnel  of  but  19,000  feet  in  length  to  drain  the  Comstock 
vein  at  1,800  feet  depth,  for  augmenting  the  net  profits  from  a 
pi'oduce  of  $15,000,000  a  year! 

The  future  of  Washoe,  indeed,  depends  entirely  on  the  execu- 
tion of  this  magnificent  enterprise.  It  is  of  vital  importance  for 
the  State  of  Nevada,  and  will  have  great  influence  on  the  neigh- 
boring California,  which  chiefly  derives  the  benelits  of  the  mines 
of  Washoe.  The  numerous  advantages  will  only  be  fully  under- 
stood when  the  work  will  be  completed.  Allow  me  to  draw 
your  attention  still  to  one  among  them,  t^everal  companies  on 
the  Comstock  vein  have  been  very  unfortunate  ;  they  either 
found  no  ore  at  all  in  their  mines,  or,  if  it  was  found  at  first, 
it  gave  out.  and  the  owners  are  discouraged  to  do  any  fur- 
ther prospecting  work.  It  is  very  probable,  that  in  deep  level^', 
some  of  these  poor  mines  may  be  among  the  best.  But  it  is  still 
of  far  greater  importance,  that  it  will  then  be  possible  to  deter- 
mine how  far  north  and  south  the  Comstock  vein  extends,  and 
bow  far  it  is  ore-bearing.  Notwithstanding  the  well  defined 
character  and  enormous  width  of  this  vein   in  the  Uncle  ?am 


28 

mine,  and  its  rich  ore,  the  vein,  which  is  very  shapeless  near 
the  surface,  has  not  yet  been  traced  with  certainty  farther  south, 
and  prospecting  on  American  Flat  is  almost  entirely  abandoned. 
Capital  is  l)eing  invested  very  unwillingly  in  the  exploration  of 
either  this  southern  or  the  northern  end  of  the  vein,  where 
equal  labor  and  capital  invested  have  not  been  rewarded.  At 
the  depth  of  1,800  feet,  all  irregularities  will  probably  have 
ceased,  and  then  these  unprofitable  mines  on  both  extreme  ends, 
may  still  prove  to  be  valuable  claims. 

Allow  me  to  congratulate  you  to  have  been  the  first  to  have 
taken  an  enterprise  of  such  vast  importance  firmly  in  your  hand. 
With  the  sincere  wish,  that  you  may  overcome  the  diflSculties 
which  you  will  no  doubt  meet  in  carrying  out  a  work  of  such 
magnitude, 

I  remain  yours  very  sincerely, 

FR.  RICHTHOFEN. 


OPINION     OF     MINING     SUPERINTENDENTS— AND 

OTHERS. 

The  undersigned,  fully  aware  of  the  importance  and  urgent 
necessity  of  providing  means  for  draining  the  Comstock  ledge  . 
by  means  of  a  deep  drain  tunnel,  and  foreseeing  the  difiiculties 
which  must  present  themselves,  before  long,  in  removing  the 
water  from  these  mines  ;  and  being  satisfied  that  the  best  inter- 
ests, of  not  only  the  owners  of  the  Comstock  ledge,  but  the  peo- 
ple at  large  of  this  State,  would  be  seriously  affected  by  neglect- 
ing this  matter  :  we  would  most  earnestly  recommend  the  imme- 
diate construction  of  such  a  work,  and  ask  the  co-operation  of  all 
parties  interested,  in  order  that  this  important  undertaking  may 
speedily  be  carried  out. 

Virginia,  February  15th,  18(^5. 

A..  E.  Davis,  Gen'l  Sup't  Ophir  S.  M.  Co. 
Harvey  Beckwith,  Sup't  Mexican  Mine. 


29 

0.  H.  Frank,  Sup't  Central  S.  M.  Co. 
Pat.  N.  McKay,  Sup't  California  S.  M.  Co. 
Jas.  Morgan,  President  Sides  Co. 

H.  H.  O'Reiley,  Sup't  White  &  Murphy  Co. 
Thomas  G.  Taylor,  Sup't  Best  &  Belcher  M.  Co. 
Charles  Bonner,  Sup't  Gould  &  Curry  S.  M.  Co. 
Sain'l  F.  Curtis,  Sup't  Savage  M,  Co. 
Chas.  L.  Peck,  Sup't  Hale  &  Norcross  S.  M.  Co. 

1.  Adams,  Sup't  Choliar  S.  M.  Co. 

Pat.  N.  McKay,  Sup't  Potosi  G.  &  S.  M.  Co. 

J.  M.  Walker,  Sup't  Bullion  M.  Co. 

P.  S.  Buckminstcr,  Sup't  Imperial  S.  M.  Co. 

John  II.  Mills,  President  of  Superior  Co. 

Robert  Apple,  Sup't  Minerva  Consolidated  M.  Co. 

R.  Graves,  Sup't  Empire  M.  &  M.  Co. 

W.  Tozer,  President  Challenge  S.  M.  Co. 

L.  U.  Colbath.  Sup't  Challenge  S.  M.  Co. 

L.  S.  Bowers,  owner  in  Gold  Hill. 

Lindauer  &  Hi.rschman,  owners  in  Gold  Hill. 

Chas.  Pioda,  owner  in  Gold  Hill. 

J.  Woodruff,  Sup't  Bacon  M.  &  M  Co. 

Wm.  Arrington,  President  Confidence  Co. 

Robert  Apple,  President  Apple  M.  &  M.  Co. 

Winters,  Kustel  &  Co.  owners  in  Gold  Hill. 

M.  A.  French,  owner  in  Gold  Hill. 

John  B.  Winters,  President  Yellow  Jacket  S.  M.  Co. 

H.  Woodcock  Sup't  Crown  Point  Co. 

F.  A.  Tritle,  President  Belcher  M.  Co. 

Wm.  Arrington,  President  Overman  Co. 

C.  C.  Thomas,  Sup't  Uncle  Sam  Co. 

Pax  ton  &  Thornburg,  Bankers. 

Wm.  Sharon,  Ag't  of  Bank  of  California. 

Jas.  H.  Latham,  Ag't  Wells,  Fargo  &  Co. 

B.  F.  Hastings  &  Co.  Bankers. 


30 

E.  Ruhling  &   Co.  Bankers. 
Almarin  B.  Paul  &  Co.      " 

Maynard  &  Flood,  "  _. 

M.  C.  Hillyer,  Trustee  Chollar  S.  M.  Co. 

A.  Meyer,  Trustee  Hale  &  Norcross  S.  M.  Co. 

D.  E.  Avery,  Gen'l  Ag't  ^ew  York  &  Washoe  M.  Co. 
J.  R.  Williams  Sup't  Sierra  Nevada  S.  M.  Co. 

W.  E.  Bidleman,  Sup't  Utah  Co. 

J.  Neely  Johnson.owner  in  Virginia  City  mines. 

H.  F.  Rice,  Ag*t  Wells,  Fargo  &  Co'8,  Carson. 

F.  Rithshoen. 
John  Cradlebaugh. 
Gillig,  Mott  &  Co. 

W.  M.  Brown,  Mining  Engineer. 

C.  V.  Beseler,       " 

John  A.  Veatch,    " 

John  White,  formerly  ot  the  United  Mines,  Cornwall. 

S.  M.  Johns,  formerly  of  the  Wheal  Prosper  Mine,  Cornwall. 

J.  F.  Lewis,  Chief  Justice  Supreme  Court. 

C.  M.  Brosnan,  Justice  of  Supreme  Court. 

W.  0.  Beatty,  Justice  of  Supreme  Court. 

Richard  Rising,  District  Judge,  Storey  County. 

R.  S.  Mesick, 

C.  Burbank, 

J.  L.  CrOv^sman,  Lieu't  Governor. 

C.  W.  Noteware,  Secretary  of  State. 

H.  W.  Nightingill,  Controller  of  State. 

E.  Rhoades,  State  Treasurer. 
N.  W.  Winton,  State  Senator. 
M.  S.  Thompson,         " 

J.  Seely, 

A.  J.  Lockwood,        " 


t 


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